1. Field of the Invention
The present invention relates to a simplified organic electronic device including a polymeric anode with high work function.
2. Description of the Related Art
Organic light-emitting devices, which are self-emitting devices, have advantages such as a wide viewing angle, excellent contrast, quick response, high brightness, excellent driving voltage characteristics, and can provide multicolored images.
A conventional organic light-emitting device includes an anode, a cathode, and an organic layer interposed between the anode and the cathode. The organic layer may include an electron injection layer (EIL), a hole transport layer (HTL), an emission layer (EML), an electron transport layer (ETL), and a cathode. When a voltage is applied between the anode and the cathode, holes injected from the anode move to the EML via the HTL, and electrons injected from the cathode move to the EML via the ETL. The holes and electrons recombine in the EML to generate excitons. When the excitons drop from an excited state to a ground state, light is emitted.
Meanwhile, much research into renewable energy has been conducted worldwide. In this regard, organic solar cells have drawn much attention because of their potential of using solar energy as a future energy source. Organic solar cells can more efficiently form a thin film and can be manufactured with low manufacturing costs compared to inorganic solar cells using silicon, and thus can be applied to various flexible devices.
The cost of indium tin oxide (ITO) electrodes that are commonly used in organic light-emitting diodes and organic solar cells has continued to increase due to exhaustion of indium, and the ITO is brittle and liable to break upon impact or bending. Thus, ITO cannot be applied to flexible devices. Although research into electrodes for replacing the ITO has been conducted, developed electrodes do not have sufficient work function. Thus, a multi-layered structure for smoothly injecting and transporting charges is formed on the electrode. However, this structure increases the amount of materials and manufacturing costs for preparing electronic devices. Thus, there is a need to develop organic electronic devices having a simplified structure with excellent performance by using a flexible electrode having high work function but not using a hole transport/extraction auxiliary layer, and to apply the organic electronic devices to flexible devices as well as conventional flat panel devices.